| San Carlos to Orbetello | 6,187.14 mi (9,957.24 km) |
| San Carlos to Oria | 6,480.38 mi (10,429.16 km) |
| San Carlos to Oristano | 6,248.58 mi (10,056.12 km) |
| San Carlos to Orta Nova | 6,379.05 mi (10,266.09 km) |
| San Carlos to Orte | 6,220.06 mi (10,010.22 km) |
| San Carlos to Ortona | 6,283.38 mi (10,112.12 km) |
| San Carlos to Orvieto | 6,197.43 mi (9,973.79 km) |
| San Carlos to Orzinuovi | 5,983.77 mi (9,629.94 km) |
| San Carlos to Osimo | 6,192.46 mi (9,965.81 km) |
| San Carlos to Ospitaletto | 5,979.08 mi (9,622.39 km) |
| San Carlos to Ostuni | 6,465.19 mi (10,404.72 km) |
| San Carlos to Ottaviano | 6,372.50 mi (10,255.55 km) |
| San Carlos to Ovada | 5,988.65 mi (9,637.80 km) |
| San Carlos to Ozieri | 6,223.97 mi (10,016.51 km) |
| San Carlos to Paceco | 6,480.38 mi (10,429.16 km) |
